Exhaust Gasket - Rear

This procedure covers the replacement of the rear exhaust gasket between the catalytic converter and muffler assembly on the 2016-2024 Hyundai Tucson with 2.5L I4 AWD engine.

Warnings

Tools required

Parts

• Rear exhaust flange gasket × 1 — Use OEM specification
• Exhaust flange bolts/nuts (if corroded) × 2 — M10 x 1.5 or equivalent OEM

Preparation

1. Park vehicle on level ground and allow exhaust system to cool completely (minimum 2 hours after engine shutdown)
2. Apply wheel chocks to front wheels
3. Raise rear of vehicle using floor jack at designated rear jacking point
4. Support vehicle securely on jack stands placed at rear pinch weld points or frame locations
5. Spray penetrating oil on rear exhaust flange bolts and allow to soak for 10-15 minutes
6. Visually locate the rear exhaust flange connection (typically located under center of vehicle near fuel tank area)

Procedure

1. 1

   Remove heat shield if present
   If a heat shield covers the rear exhaust flange area, remove the retaining bolts using a 10mm socket. Set the heat shield aside for reinstallation.
   Torque spec

   Heat Shield Bolts10 Nm (7 lb-ft)
2. 2

   Support rear exhaust section
   Position a floor jack or exhaust support stand under the rear muffler section to prevent the exhaust from dropping when the flange is separated. Apply just enough pressure to support the weight without lifting.
   ⚠Failure to support the exhaust may cause it to drop suddenly and damage hanger mounts or the flange connection.
3. 3

   Remove rear exhaust flange bolts
   Using a 17mm deep socket with extension, remove the two bolts securing the rear exhaust flange connection. Work slowly and apply additional penetrating oil if resistance is encountered. If bolts are severely corroded or begin to strip, use a 6-point socket or apply heat carefully with a propane torch.
   ⚠Exhaust bolts may be severely corroded. If a bolt breaks, you may need to drill out the stud and re-tap the flange or use a replacement clamp-style connection.
4. 4

   Separate exhaust flange
   Carefully pull the rear exhaust section away from the mid-pipe flange. You may need to use a pry bar to gently separate the connection if the old gasket is stuck. Lower the rear section slightly using the support jack to create clearance.
   ℹ️The exhaust may still be supported by rubber hanger mounts. Do not force separation if significant resistance is felt.
5. 5

   Remove old gasket and clean surfaces
   Remove and discard the old exhaust gasket from the flange connection. Use a wire brush to thoroughly clean both flange mating surfaces, removing all carbon deposits, rust, and old gasket material. Ensure both surfaces are flat and free of debris.
   ℹ️A clean, flat sealing surface is critical for preventing exhaust leaks. Spend adequate time on surface preparation.
6. 6

   Inspect flange and studs
   Inspect both exhaust flanges for cracks, warping, or damage. Check that the bolt holes are not elongated or stripped. If studs are present instead of bolts, verify they are not damaged or cross-threaded. Replace any damaged hardware before proceeding.
7. 7

   Install new gasket
   Position the new rear exhaust gasket between the two flange surfaces. Ensure the gasket is properly oriented and aligned with the bolt holes. Most gaskets have a specific orientation with a raised bead or directional indicator.
   ℹ️Some gaskets have a metal reinforcement ring that should face the front (catalytic converter side) of the vehicle. Verify orientation before installation.
8. 8

   Align and reconnect exhaust sections
   Using the support jack, raise the rear exhaust section and align it with the mid-pipe flange. Ensure the gasket remains properly positioned. Align the bolt holes on both flanges. You may need to adjust the position of the rear muffler section slightly to achieve proper alignment.
9. 9

   Install and torque flange bolts
   Apply a thin coat of anti-seize compound to the threads of the flange bolts. Thread the bolts by hand to ensure proper engagement. Using a 17mm socket, tighten the bolts in an alternating pattern (first one bolt snug, then the opposite bolt) to draw the flanges together evenly. Final torque both bolts to specification using a calibrated torque wrench.
   Torque spec

   Exhaust Flange Bolts45 Nm (33 lb-ft)
10. 10

    Reinstall heat shield
    If a heat shield was removed in step 1, reposition it over the flange connection and install the retaining bolts. Torque to specification.
    Torque spec

    Heat Shield Bolts10 Nm (7 lb-ft)
11. 11

    Remove exhaust support and lower vehicle
    Carefully remove the support jack or stand from under the rear exhaust section. Verify all exhaust hangers are properly seated in their rubber mounts. Remove jack stands and lower the vehicle to the ground.

Reassembly

1. Ensure all exhaust rubber hanger mounts are properly engaged and not twisted
2. Verify no tools or parts were left under the vehicle
3. Check that the exhaust system hangs evenly with proper ground clearance

Verification

• Start the engine and allow it to idle for 2-3 minutes
• Carefully inspect the rear flange connection for any signs of exhaust leaks (visible smoke, hissing sounds, or soot accumulation)
• Rev the engine to 2000-2500 RPM and recheck for leaks at the flange
• If a leak is detected, allow the exhaust to cool, check torque values, and verify gasket installation orientation
• Perform a short test drive and recheck the flange connection for leaks after the exhaust has heated and cooled through one cycle

Related trouble codes on this vehicle

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